Most shocking, perhaps, are reports of large parasitic worms, some measuring 11 inches, recovered from his intestines.

"An estimated 5 million people in North Korea have intestinal roundworms. That's 20 percent of the population," said Dr. Peter Hotez, the dean of the National School of Tropical Medicine at Baylor.

Doctors found the parasites — likely Ascaris roundworms — while repairing intestinal damage from multiple bullet wounds the soldier sustained during his escape. The eggs of these worms are frequently found in the soil, especially in developing countries that use human waste as an inexpensive fertilizer. Once inside the body, these eggs hatch to form larvae that eventually develop into large worms that infect the small intestine. They can grow to more than 13 inches long.

Play

How the North Korean defector escaped across the DMZ

Despite the size of these creatures, Ascaris roundworm infections may not be accompanied by noticeable symptoms. However, Hotez said, they can lead to malnutrition in the infected. In children, this can lead to developmental delays and short stature.

"Instead of feeding the kid, you're feeding the worms," said Hotez. "They rob children of nutrition."

Multiple large worms in an infected person can cause intestinal blockages, and the worms can travel to the nearby liver, gallbladder, or pancreas and cause damage and inflammation to those organs, Hotez said.

While dramatic in appearance, roundworm infections are easy to treat, generally requiring only a single dose of anti-parasitic medication.

Likewise, another parasitic worm infection the soldier reportedly had, Toxocara, is also fairly easily treated. Toxocara is a parasite similar to Ascaris, though it is normally found in the intestines of dogs and cats; the worms do not usually grow as large in the intestines of humans. The larvae of these parasites often migrate to other organs in the body — often the liver, brain, lungs and eyes — causing damage.

But even more problematic than the parasitic infections is the soldier's reported hepatitis B, a viral infection of the liver that can lead to life-threatening cirrhosis if untreated.

His case is just the latest of health problems among hundreds of other refugees and defectors from North Korea. Past reports have shown that many who have fled the country suffer from those maladies, as well as tuberculosis, a common and frequently difficult-to-treat lung infection.

Studies comparing North Korean defectors with other refugee populations found they were more likely to be underweight — and one estimated that about one-third of North Korean children under age 5 are malnourished. Dental and vision problems, such as cataracts, are also frequently reported.

Though the reclusive nature of the country limits what is known about its health problems, Hotez said such health issues are common in other places with devastating economic conditions.

"These are not unique to North Korea," he said. "These are all infections that are extremely common in the poorest parts of Asia. Toxocara is found in poor neighborhoods in the United States as well."

Worm eradication programs were successfully implemented in South Korea after the Korean War, Hotez added, and pharmaceutical companies have been willing to donate supplies of anti-parasitic drugs to countries in need.

Other illnesses afflicting North Koreans, such as hepatitis B, are preventable through vaccination programs.

But North Korea's tense political and economic relations with other nations make it complicated to assess and attempt eradication of such problems in the country.